RAID 5 SSD array?

[fabulouscoops]

After buying a 1 TB SSD for my main computer, I find myself with 3 120 GB Mushkin Cronos drives, two of which were running the OS's on my main and second rig (the other one was a back up still in the pkg.
I have been thinking of running a RAID 5 array but see a lot of talk online about too many writes in RAID 5 shortening the life of an SSD (And the opposite side saying the problem is overblown). I have also seen where people have split three drives into two partitions each and run RAID 10 on six partitions.
Another potential problem is controllers not being able to keep up with blazing SSD RAID speeds.
In the past, I have run RAID 5 on three 35 GB raptors and have experience with RAID 1 and 0 but not with SSDs.

Opinions and discussion would be welcome.

 

[Blaylock]

It really depends on what your storage needs are. If you need the added security of parity then RAID 5 is the way to go. If you're looking for max speed then it is not. As far as the drives dying prematurely from excessive writes I believe, but could be wrong here, that it was an issue with older SSD's. There may be a few stragglers that have this issue but I think most have been phased out. You might want to research this a bit more.

You're really only looking at 360GB of storage space. That's really not a ton of space. Personally, I would just run RAID 1 or 0 depending what these drives will be used for.

 

[EarthDog]

Writes on SSDs haven't been a worry in generations, really. Let's get that out of the way.

As far as should I... that is up to you. I wouldn't bother putting SSDs in RAID regardless. They are fast as is, and RAID isn't a backup. I don't see the point of a complicated RAID array (partitioning etc).

 

[Mpegger]

You probably already have spare drives lying around, so if you're after blazing fast speed for a specific application, I'd just got RAID0 with the SSDs, but make sure you have a comprehensive backup operation in place.

Of course, a better option would be to just add a m.2 nVME over PCIE to your system and call it a day, but that would cost additional money (especially if your board doesn't support m.2 nVME).

 

[fabulouscoops]

Space-wise 120 GB was no longer cutting it for Windows 7 + programs (games are on a separate drive). I am finally upgrading to Windows 10 and wanted to at least double my OS drive on the second PC without spending more money. I have these three identical drives but I will never run my OS on RAID 0, and RAID 1 is still only 120 GB. So it is more about space and parity than speed.
Thanks for your input, I think I will go ahead and use the three drives.

 

[Mpegger]

If you go RAID5, you would only have 240GB and even that would feel abit cramped on W10, and as other's have said, RAIDx is not a backup. If a drive did fail, are you really gonna go out and buy another 120GB drive to restore that RAID, or save up some money so by the time a replacement is needed, you could easily afford a good 500GB+ SSD/nVME?

RAID0 360GB would give you some breathing room and more speed to boot (pun intended). If you have any mechanical drives laying around larger then that, you could easily use any freely available backup program to image that RAID array to a dedicated backup drive on a regular basis. You could even skip the imaging, and just go with backing up essential files, as having to re-install W10 is a breeze. It actually takes longer to restore a backup, then it does to re-install W10 and any individual programs you had installed previously.

Just enjoy the slightly better performance from the RAID0, and then upgrade your storage later on down the line. Unless those SSDs are really old and been trashed with constant writes at near full capacity for tens of thousands of hours, they will probably continue to chug along just fine by the time you replace them with a single drive in the future.

 

[Woomack]

RAID5 is not recommended for SSD. It's actually barely ever used because of the high amount of writes. RAID5 all the time perform writes. In a typical situation, RAID10 is recommended for SSD. RAID5 is good for large storage on HDD.

 

[DaPoets]

Yeah I would have to put in my 2 cents and say for a few SSDs that you have raid 0 is nearly as safe as not using raid at all. An SSD failing is statistically less likely than a mechanical hard drive. With that said unless you are doing some seriously large file movements (and it's unlikely w/ those small drives) that putting SSDs in Raid 0 or any other Raid format will give you no real world benefits. If you need redundancy for that small of a storage space I guess RAID 10 is ok but at that point I would just use the SSDs w/ out raid and ensure I have my cloud storage setup correctly for backups. (Google Drive, Microsoft One Drive, etc)

 

[ratbuddy]

RAID5 is not recommended for SSD. It's actually barely ever used because of the high amount of writes. RAID5 all the time perform writes. In a typical situation, RAID10 is recommended for SSD. RAID5 is good for large storage on HDD.

RAID 5 is no longer good for anything other than small drives, it's been obsolete for several years now. RAID 6 or ZFS with two spares (RAID-Z2) should be considered the minimum if you don't want to lose data when a drive fails.

 

[Blaylock]

I don't necessarily agree with this statement.

 

[Janus67]

I agree with ratbuddy on that, the time to resliver larger drives is a risk (especially with how heavy reslivering is on existing drives) that the risk for losing an additional drive past the 1 parity drive in a RAID5 to lead to a loss of all data leads to the general recommendation of a RAID6/Z2 or RAID10-type setup.

Obviously this is including the full knowledge that RAID is redundancy and not a backup. So if something isn't 100% critical and everything is backed up but you want a bit of redundancy RAID5 can suffice, but in many larger scale deployments RAID5 is no longer used.

 

[Blaylock]

I think what may be the question is what defines a large drive. Obviously raid 6 is greater than raid 5 and zfs has its benefits as well, I don't believe raid 5 is quite obsolete. A structured backup schedule is definitely a must though.

 

[Janus67]

I think what may be the question is what defines a large drive. Obviously raid 6 is greater than raid 5 and zfs has its benefits as well, I don't believe raid 5 is quite obsolete. A structured backup schedule is definitely a must though.

I think I started reading articles/blogs/etc that most people when they started using 2TB drives they moved to RAID6 for the additional parity drive. I started doing so when I moved to a 8x4TB NAS setup (ZFS2 on FreeNAS).

 

[fabulouscoops]

I appreciate the discussion on this and you've convinced me its not the greatest idea.
Mpegger's advice prompted me to look into NVMe M.2 and I went ahead and bought a 500 GB Samsung 970 EVO plus. So I will use that in my main PC and the 1 TB SSD in the second PC. I will find a use for the 120 GB SSDs maybe as back up drives in an external drive docking station instead of the USB thumb drives I use now.
Now I have to decide if I clone the system drive to a smaller drive or just reinstall Windows from the back up.

 

[Mpegger]

Look into PrimoCache if you wanna put those 120GiB SSDs to use. You can use it as a cache drive for any mechanical drives you have installed in your system. It's great for a dedicated game drive that's a slow, but large spinner.

 

[ratbuddy]

Look into PrimoCache if you wanna put those 120GiB SSDs to use. You can use it as a cache drive for any mechanical drives you have installed in your system. It's great for a dedicated game drive that's a slow, but large spinner.

This, I can highly recommend. My main system is all SSD, and I still run a 32GB PrimoCache using RAM. Amazing little piece of software!

I agree with the above as well - once you're at 2TB drives or so, RAID 5 is no longer a good idea if you're running it for the ability to lose a drive and not lose data.

 

[fabulouscoops]

My "Steam" drive is a 2x2TB RAID 0 array and does about 300 MB/sec (all scores are ATTO)
The SSD I would use as a cache is giving about 500 MB/sec. I have read that Primocache would give 80% of the SSD speed. So no great improvement.
But the M.2 drive is reading 3,000 MB/sec
I am definitely considering using that as an L2 cache if I buy the license. And I have 16 Gig of RAM to play with.
But for now, I am moving frequently used games to the C drive.
The 120 GB SSDs I started this thread asking about I could maybe use in my wife's PC

 

[Mpegger]

I've never read about a 80% speed of a SSD. It still reads at the speed of the SSD, but of course, there will be some added latency because of the intercepted reads. 80% seems too low though, as the information on what blocks are cached is kept in ram; the size of the cache (including block size) will use additional ram to keep the blocks being cached in ram.

 

[fabulouscoops]

I've never read about a 80% speed of a SSD. It still reads at the speed of the SSD, but of course, there will be some added latency because of the intercepted reads. 80% seems too low though, as the information on what blocks are cached is kept in ram; the size of the cache (including block size) will use additional ram to keep the blocks being cached in ram.

Saw that on the Romex forum
http://www.romexsoftware.com/bbs2/en-us/viewtopic.php?t=4525

 

[ratbuddy]

Cached reads from the SSD will have MUCH lower latency than physical reads from the spinning drives, it's not just about sustained sequential transfer rates.